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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Network60.22.0.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
60.22.0.0
Broadcast address
60.22.31.255
First usable
60.22.0.1
Last usable
60.22.31.254
Usable hosts
8,190 (8,192 less the network and broadcast addresses)
Subnet mask
255.255.224.0
Wildcard mask
0.0.31.255 (Cisco ACLs, OSPF)
Prefix length
/19
Type
Public public
Old class
A (default /8)
As numbers
Hex 3C160000 · Integer 1008074752 to 1008082943
Reverse DNS zones
0.22.60.in-addr.arpa
1.22.60.in-addr.arpa
2.22.60.in-addr.arpa
3.22.60.in-addr.arpa
4.22.60.in-addr.arpa
5.22.60.in-addr.arpa
6.22.60.in-addr.arpa
7.22.60.in-addr.arpa
8.22.60.in-addr.arpa
9.22.60.in-addr.arpa
10.22.60.in-addr.arpa
11.22.60.in-addr.arpa
12.22.60.in-addr.arpa
13.22.60.in-addr.arpa
14.22.60.in-addr.arpa
15.22.60.in-addr.arpa
and 16 more
/19 is not on a 8-bit boundary, so it takes 32 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00111100.00010110.00000000.0000000060.22.0.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network00111100.00010110.00000000.0000000060.22.0.0
Broadcast00111100.00010110.00011111.1111111160.22.31.255
Split into smaller subnets/29
/20 (2)/21 (4)/22 (8)/23 (16)/24 (32)/25 (64)/26 (128)/27 (256)/28 (512)/29 (1,024)/30 (2,048)/31 (4,096)

60.22.0.0/19 makes 1,024 subnets of /29; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
160.22.0.0/2960.22.0.1 to 60.22.0.660.22.0.76
260.22.0.8/2960.22.0.9 to 60.22.0.1460.22.0.156
360.22.0.16/2960.22.0.17 to 60.22.0.2260.22.0.236
460.22.0.24/2960.22.0.25 to 60.22.0.3060.22.0.316
560.22.0.32/2960.22.0.33 to 60.22.0.3860.22.0.396
660.22.0.40/2960.22.0.41 to 60.22.0.4660.22.0.476
760.22.0.48/2960.22.0.49 to 60.22.0.5460.22.0.556
860.22.0.56/2960.22.0.57 to 60.22.0.6260.22.0.636
960.22.0.64/2960.22.0.65 to 60.22.0.7060.22.0.716
1060.22.0.72/2960.22.0.73 to 60.22.0.7860.22.0.796
1160.22.0.80/2960.22.0.81 to 60.22.0.8660.22.0.876
1260.22.0.88/2960.22.0.89 to 60.22.0.9460.22.0.956
1360.22.0.96/2960.22.0.97 to 60.22.0.10260.22.0.1036
1460.22.0.104/2960.22.0.105 to 60.22.0.11060.22.0.1116
1560.22.0.112/2960.22.0.113 to 60.22.0.11860.22.0.1196
1660.22.0.120/2960.22.0.121 to 60.22.0.12660.22.0.1276
1760.22.0.128/2960.22.0.129 to 60.22.0.13460.22.0.1356
1860.22.0.136/2960.22.0.137 to 60.22.0.14260.22.0.1436
1960.22.0.144/2960.22.0.145 to 60.22.0.15060.22.0.1516
2060.22.0.152/2960.22.0.153 to 60.22.0.15860.22.0.1596
2160.22.0.160/2960.22.0.161 to 60.22.0.16660.22.0.1676
2260.22.0.168/2960.22.0.169 to 60.22.0.17460.22.0.1756
2360.22.0.176/2960.22.0.177 to 60.22.0.18260.22.0.1836
2460.22.0.184/2960.22.0.185 to 60.22.0.19060.22.0.1916
2560.22.0.192/2960.22.0.193 to 60.22.0.19860.22.0.1996
2660.22.0.200/2960.22.0.201 to 60.22.0.20660.22.0.2076
2760.22.0.208/2960.22.0.209 to 60.22.0.21460.22.0.2156
2860.22.0.216/2960.22.0.217 to 60.22.0.22260.22.0.2236
2960.22.0.224/2960.22.0.225 to 60.22.0.23060.22.0.2316
3060.22.0.232/2960.22.0.233 to 60.22.0.23860.22.0.2396
3160.22.0.240/2960.22.0.241 to 60.22.0.24660.22.0.2476
3260.22.0.248/2960.22.0.249 to 60.22.0.25460.22.0.2556
3360.22.1.0/2960.22.1.1 to 60.22.1.660.22.1.76
3460.22.1.8/2960.22.1.9 to 60.22.1.1460.22.1.156
3560.22.1.16/2960.22.1.17 to 60.22.1.2260.22.1.236
3660.22.1.24/2960.22.1.25 to 60.22.1.3060.22.1.316
3760.22.1.32/2960.22.1.33 to 60.22.1.3860.22.1.396
3860.22.1.40/2960.22.1.41 to 60.22.1.4660.22.1.476
3960.22.1.48/2960.22.1.49 to 60.22.1.5460.22.1.556
4060.22.1.56/2960.22.1.57 to 60.22.1.6260.22.1.636
4160.22.1.64/2960.22.1.65 to 60.22.1.7060.22.1.716
4260.22.1.72/2960.22.1.73 to 60.22.1.7860.22.1.796
4360.22.1.80/2960.22.1.81 to 60.22.1.8660.22.1.876
4460.22.1.88/2960.22.1.89 to 60.22.1.9460.22.1.956
4560.22.1.96/2960.22.1.97 to 60.22.1.10260.22.1.1036
4660.22.1.104/2960.22.1.105 to 60.22.1.11060.22.1.1116
4760.22.1.112/2960.22.1.113 to 60.22.1.11860.22.1.1196
4860.22.1.120/2960.22.1.121 to 60.22.1.12660.22.1.1276
4960.22.1.128/2960.22.1.129 to 60.22.1.13460.22.1.1356
5060.22.1.136/2960.22.1.137 to 60.22.1.14260.22.1.1436
5160.22.1.144/2960.22.1.145 to 60.22.1.15060.22.1.1516
5260.22.1.152/2960.22.1.153 to 60.22.1.15860.22.1.1596
5360.22.1.160/2960.22.1.161 to 60.22.1.16660.22.1.1676
5460.22.1.168/2960.22.1.169 to 60.22.1.17460.22.1.1756
5560.22.1.176/2960.22.1.177 to 60.22.1.18260.22.1.1836
5660.22.1.184/2960.22.1.185 to 60.22.1.19060.22.1.1916
5760.22.1.192/2960.22.1.193 to 60.22.1.19860.22.1.1996
5860.22.1.200/2960.22.1.201 to 60.22.1.20660.22.1.2076
5960.22.1.208/2960.22.1.209 to 60.22.1.21460.22.1.2156
6060.22.1.216/2960.22.1.217 to 60.22.1.22260.22.1.2236
6160.22.1.224/2960.22.1.225 to 60.22.1.23060.22.1.2316
6260.22.1.232/2960.22.1.233 to 60.22.1.23860.22.1.2396
6360.22.1.240/2960.22.1.241 to 60.22.1.24660.22.1.2476
6460.22.1.248/2960.22.1.249 to 60.22.1.25460.22.1.2556
6560.22.2.0/2960.22.2.1 to 60.22.2.660.22.2.76
6660.22.2.8/2960.22.2.9 to 60.22.2.1460.22.2.156
6760.22.2.16/2960.22.2.17 to 60.22.2.2260.22.2.236
6860.22.2.24/2960.22.2.25 to 60.22.2.3060.22.2.316
6960.22.2.32/2960.22.2.33 to 60.22.2.3860.22.2.396
7060.22.2.40/2960.22.2.41 to 60.22.2.4660.22.2.476
7160.22.2.48/2960.22.2.49 to 60.22.2.5460.22.2.556
7260.22.2.56/2960.22.2.57 to 60.22.2.6260.22.2.636
7360.22.2.64/2960.22.2.65 to 60.22.2.7060.22.2.716
7460.22.2.72/2960.22.2.73 to 60.22.2.7860.22.2.796
7560.22.2.80/2960.22.2.81 to 60.22.2.8660.22.2.876
7660.22.2.88/2960.22.2.89 to 60.22.2.9460.22.2.956
7760.22.2.96/2960.22.2.97 to 60.22.2.10260.22.2.1036
7860.22.2.104/2960.22.2.105 to 60.22.2.11060.22.2.1116
7960.22.2.112/2960.22.2.113 to 60.22.2.11860.22.2.1196
8060.22.2.120/2960.22.2.121 to 60.22.2.12660.22.2.1276
8160.22.2.128/2960.22.2.129 to 60.22.2.13460.22.2.1356
8260.22.2.136/2960.22.2.137 to 60.22.2.14260.22.2.1436
8360.22.2.144/2960.22.2.145 to 60.22.2.15060.22.2.1516
8460.22.2.152/2960.22.2.153 to 60.22.2.15860.22.2.1596
8560.22.2.160/2960.22.2.161 to 60.22.2.16660.22.2.1676
8660.22.2.168/2960.22.2.169 to 60.22.2.17460.22.2.1756
8760.22.2.176/2960.22.2.177 to 60.22.2.18260.22.2.1836
8860.22.2.184/2960.22.2.185 to 60.22.2.19060.22.2.1916
8960.22.2.192/2960.22.2.193 to 60.22.2.19860.22.2.1996
9060.22.2.200/2960.22.2.201 to 60.22.2.20660.22.2.2076
9160.22.2.208/2960.22.2.209 to 60.22.2.21460.22.2.2156
9260.22.2.216/2960.22.2.217 to 60.22.2.22260.22.2.2236
9360.22.2.224/2960.22.2.225 to 60.22.2.23060.22.2.2316
9460.22.2.232/2960.22.2.233 to 60.22.2.23860.22.2.2396
9560.22.2.240/2960.22.2.241 to 60.22.2.24660.22.2.2476
9660.22.2.248/2960.22.2.249 to 60.22.2.25460.22.2.2556
9760.22.3.0/2960.22.3.1 to 60.22.3.660.22.3.76
9860.22.3.8/2960.22.3.9 to 60.22.3.1460.22.3.156
9960.22.3.16/2960.22.3.17 to 60.22.3.2260.22.3.236
10060.22.3.24/2960.22.3.25 to 60.22.3.3060.22.3.316
10160.22.3.32/2960.22.3.33 to 60.22.3.3860.22.3.396
10260.22.3.40/2960.22.3.41 to 60.22.3.4660.22.3.476
10360.22.3.48/2960.22.3.49 to 60.22.3.5460.22.3.556
10460.22.3.56/2960.22.3.57 to 60.22.3.6260.22.3.636
10560.22.3.64/2960.22.3.65 to 60.22.3.7060.22.3.716
10660.22.3.72/2960.22.3.73 to 60.22.3.7860.22.3.796
10760.22.3.80/2960.22.3.81 to 60.22.3.8660.22.3.876
10860.22.3.88/2960.22.3.89 to 60.22.3.9460.22.3.956
10960.22.3.96/2960.22.3.97 to 60.22.3.10260.22.3.1036
11060.22.3.104/2960.22.3.105 to 60.22.3.11060.22.3.1116
11160.22.3.112/2960.22.3.113 to 60.22.3.11860.22.3.1196
11260.22.3.120/2960.22.3.121 to 60.22.3.12660.22.3.1276
11360.22.3.128/2960.22.3.129 to 60.22.3.13460.22.3.1356
11460.22.3.136/2960.22.3.137 to 60.22.3.14260.22.3.1436
11560.22.3.144/2960.22.3.145 to 60.22.3.15060.22.3.1516
11660.22.3.152/2960.22.3.153 to 60.22.3.15860.22.3.1596
11760.22.3.160/2960.22.3.161 to 60.22.3.16660.22.3.1676
11860.22.3.168/2960.22.3.169 to 60.22.3.17460.22.3.1756
11960.22.3.176/2960.22.3.177 to 60.22.3.18260.22.3.1836
12060.22.3.184/2960.22.3.185 to 60.22.3.19060.22.3.1916
12160.22.3.192/2960.22.3.193 to 60.22.3.19860.22.3.1996
12260.22.3.200/2960.22.3.201 to 60.22.3.20660.22.3.2076
12360.22.3.208/2960.22.3.209 to 60.22.3.21460.22.3.2156
12460.22.3.216/2960.22.3.217 to 60.22.3.22260.22.3.2236
12560.22.3.224/2960.22.3.225 to 60.22.3.23060.22.3.2316
12660.22.3.232/2960.22.3.233 to 60.22.3.23860.22.3.2396
12760.22.3.240/2960.22.3.241 to 60.22.3.24660.22.3.2476
12860.22.3.248/2960.22.3.249 to 60.22.3.25460.22.3.2556
12960.22.4.0/2960.22.4.1 to 60.22.4.660.22.4.76
13060.22.4.8/2960.22.4.9 to 60.22.4.1460.22.4.156
13160.22.4.16/2960.22.4.17 to 60.22.4.2260.22.4.236
13260.22.4.24/2960.22.4.25 to 60.22.4.3060.22.4.316
13360.22.4.32/2960.22.4.33 to 60.22.4.3860.22.4.396
13460.22.4.40/2960.22.4.41 to 60.22.4.4660.22.4.476
13560.22.4.48/2960.22.4.49 to 60.22.4.5460.22.4.556
13660.22.4.56/2960.22.4.57 to 60.22.4.6260.22.4.636
13760.22.4.64/2960.22.4.65 to 60.22.4.7060.22.4.716
13860.22.4.72/2960.22.4.73 to 60.22.4.7860.22.4.796
13960.22.4.80/2960.22.4.81 to 60.22.4.8660.22.4.876
14060.22.4.88/2960.22.4.89 to 60.22.4.9460.22.4.956
14160.22.4.96/2960.22.4.97 to 60.22.4.10260.22.4.1036
14260.22.4.104/2960.22.4.105 to 60.22.4.11060.22.4.1116
14360.22.4.112/2960.22.4.113 to 60.22.4.11860.22.4.1196
14460.22.4.120/2960.22.4.121 to 60.22.4.12660.22.4.1276
14560.22.4.128/2960.22.4.129 to 60.22.4.13460.22.4.1356
14660.22.4.136/2960.22.4.137 to 60.22.4.14260.22.4.1436
14760.22.4.144/2960.22.4.145 to 60.22.4.15060.22.4.1516
14860.22.4.152/2960.22.4.153 to 60.22.4.15860.22.4.1596
14960.22.4.160/2960.22.4.161 to 60.22.4.16660.22.4.1676
15060.22.4.168/2960.22.4.169 to 60.22.4.17460.22.4.1756
15160.22.4.176/2960.22.4.177 to 60.22.4.18260.22.4.1836
15260.22.4.184/2960.22.4.185 to 60.22.4.19060.22.4.1916
15360.22.4.192/2960.22.4.193 to 60.22.4.19860.22.4.1996
15460.22.4.200/2960.22.4.201 to 60.22.4.20660.22.4.2076
15560.22.4.208/2960.22.4.209 to 60.22.4.21460.22.4.2156
15660.22.4.216/2960.22.4.217 to 60.22.4.22260.22.4.2236
15760.22.4.224/2960.22.4.225 to 60.22.4.23060.22.4.2316
15860.22.4.232/2960.22.4.233 to 60.22.4.23860.22.4.2396
15960.22.4.240/2960.22.4.241 to 60.22.4.24660.22.4.2476
16060.22.4.248/2960.22.4.249 to 60.22.4.25460.22.4.2556
16160.22.5.0/2960.22.5.1 to 60.22.5.660.22.5.76
16260.22.5.8/2960.22.5.9 to 60.22.5.1460.22.5.156
16360.22.5.16/2960.22.5.17 to 60.22.5.2260.22.5.236
16460.22.5.24/2960.22.5.25 to 60.22.5.3060.22.5.316
16560.22.5.32/2960.22.5.33 to 60.22.5.3860.22.5.396
16660.22.5.40/2960.22.5.41 to 60.22.5.4660.22.5.476
16760.22.5.48/2960.22.5.49 to 60.22.5.5460.22.5.556
16860.22.5.56/2960.22.5.57 to 60.22.5.6260.22.5.636
16960.22.5.64/2960.22.5.65 to 60.22.5.7060.22.5.716
17060.22.5.72/2960.22.5.73 to 60.22.5.7860.22.5.796
17160.22.5.80/2960.22.5.81 to 60.22.5.8660.22.5.876
17260.22.5.88/2960.22.5.89 to 60.22.5.9460.22.5.956
17360.22.5.96/2960.22.5.97 to 60.22.5.10260.22.5.1036
17460.22.5.104/2960.22.5.105 to 60.22.5.11060.22.5.1116
17560.22.5.112/2960.22.5.113 to 60.22.5.11860.22.5.1196
17660.22.5.120/2960.22.5.121 to 60.22.5.12660.22.5.1276
17760.22.5.128/2960.22.5.129 to 60.22.5.13460.22.5.1356
17860.22.5.136/2960.22.5.137 to 60.22.5.14260.22.5.1436
17960.22.5.144/2960.22.5.145 to 60.22.5.15060.22.5.1516
18060.22.5.152/2960.22.5.153 to 60.22.5.15860.22.5.1596
18160.22.5.160/2960.22.5.161 to 60.22.5.16660.22.5.1676
18260.22.5.168/2960.22.5.169 to 60.22.5.17460.22.5.1756
18360.22.5.176/2960.22.5.177 to 60.22.5.18260.22.5.1836
18460.22.5.184/2960.22.5.185 to 60.22.5.19060.22.5.1916
18560.22.5.192/2960.22.5.193 to 60.22.5.19860.22.5.1996
18660.22.5.200/2960.22.5.201 to 60.22.5.20660.22.5.2076
18760.22.5.208/2960.22.5.209 to 60.22.5.21460.22.5.2156
18860.22.5.216/2960.22.5.217 to 60.22.5.22260.22.5.2236
18960.22.5.224/2960.22.5.225 to 60.22.5.23060.22.5.2316
19060.22.5.232/2960.22.5.233 to 60.22.5.23860.22.5.2396
19160.22.5.240/2960.22.5.241 to 60.22.5.24660.22.5.2476
19260.22.5.248/2960.22.5.249 to 60.22.5.25460.22.5.2556
19360.22.6.0/2960.22.6.1 to 60.22.6.660.22.6.76
19460.22.6.8/2960.22.6.9 to 60.22.6.1460.22.6.156
19560.22.6.16/2960.22.6.17 to 60.22.6.2260.22.6.236
19660.22.6.24/2960.22.6.25 to 60.22.6.3060.22.6.316
19760.22.6.32/2960.22.6.33 to 60.22.6.3860.22.6.396
19860.22.6.40/2960.22.6.41 to 60.22.6.4660.22.6.476
19960.22.6.48/2960.22.6.49 to 60.22.6.5460.22.6.556
20060.22.6.56/2960.22.6.57 to 60.22.6.6260.22.6.636
20160.22.6.64/2960.22.6.65 to 60.22.6.7060.22.6.716
20260.22.6.72/2960.22.6.73 to 60.22.6.7860.22.6.796
20360.22.6.80/2960.22.6.81 to 60.22.6.8660.22.6.876
20460.22.6.88/2960.22.6.89 to 60.22.6.9460.22.6.956
20560.22.6.96/2960.22.6.97 to 60.22.6.10260.22.6.1036
20660.22.6.104/2960.22.6.105 to 60.22.6.11060.22.6.1116
20760.22.6.112/2960.22.6.113 to 60.22.6.11860.22.6.1196
20860.22.6.120/2960.22.6.121 to 60.22.6.12660.22.6.1276
20960.22.6.128/2960.22.6.129 to 60.22.6.13460.22.6.1356
21060.22.6.136/2960.22.6.137 to 60.22.6.14260.22.6.1436
21160.22.6.144/2960.22.6.145 to 60.22.6.15060.22.6.1516
21260.22.6.152/2960.22.6.153 to 60.22.6.15860.22.6.1596
21360.22.6.160/2960.22.6.161 to 60.22.6.16660.22.6.1676
21460.22.6.168/2960.22.6.169 to 60.22.6.17460.22.6.1756
21560.22.6.176/2960.22.6.177 to 60.22.6.18260.22.6.1836
21660.22.6.184/2960.22.6.185 to 60.22.6.19060.22.6.1916
21760.22.6.192/2960.22.6.193 to 60.22.6.19860.22.6.1996
21860.22.6.200/2960.22.6.201 to 60.22.6.20660.22.6.2076
21960.22.6.208/2960.22.6.209 to 60.22.6.21460.22.6.2156
22060.22.6.216/2960.22.6.217 to 60.22.6.22260.22.6.2236
22160.22.6.224/2960.22.6.225 to 60.22.6.23060.22.6.2316
22260.22.6.232/2960.22.6.233 to 60.22.6.23860.22.6.2396
22360.22.6.240/2960.22.6.241 to 60.22.6.24660.22.6.2476
22460.22.6.248/2960.22.6.249 to 60.22.6.25460.22.6.2556
22560.22.7.0/2960.22.7.1 to 60.22.7.660.22.7.76
22660.22.7.8/2960.22.7.9 to 60.22.7.1460.22.7.156
22760.22.7.16/2960.22.7.17 to 60.22.7.2260.22.7.236
22860.22.7.24/2960.22.7.25 to 60.22.7.3060.22.7.316
22960.22.7.32/2960.22.7.33 to 60.22.7.3860.22.7.396
23060.22.7.40/2960.22.7.41 to 60.22.7.4660.22.7.476
23160.22.7.48/2960.22.7.49 to 60.22.7.5460.22.7.556
23260.22.7.56/2960.22.7.57 to 60.22.7.6260.22.7.636
23360.22.7.64/2960.22.7.65 to 60.22.7.7060.22.7.716
23460.22.7.72/2960.22.7.73 to 60.22.7.7860.22.7.796
23560.22.7.80/2960.22.7.81 to 60.22.7.8660.22.7.876
23660.22.7.88/2960.22.7.89 to 60.22.7.9460.22.7.956
23760.22.7.96/2960.22.7.97 to 60.22.7.10260.22.7.1036
23860.22.7.104/2960.22.7.105 to 60.22.7.11060.22.7.1116
23960.22.7.112/2960.22.7.113 to 60.22.7.11860.22.7.1196
24060.22.7.120/2960.22.7.121 to 60.22.7.12660.22.7.1276
24160.22.7.128/2960.22.7.129 to 60.22.7.13460.22.7.1356
24260.22.7.136/2960.22.7.137 to 60.22.7.14260.22.7.1436
24360.22.7.144/2960.22.7.145 to 60.22.7.15060.22.7.1516
24460.22.7.152/2960.22.7.153 to 60.22.7.15860.22.7.1596
24560.22.7.160/2960.22.7.161 to 60.22.7.16660.22.7.1676
24660.22.7.168/2960.22.7.169 to 60.22.7.17460.22.7.1756
24760.22.7.176/2960.22.7.177 to 60.22.7.18260.22.7.1836
24860.22.7.184/2960.22.7.185 to 60.22.7.19060.22.7.1916
24960.22.7.192/2960.22.7.193 to 60.22.7.19860.22.7.1996
25060.22.7.200/2960.22.7.201 to 60.22.7.20660.22.7.2076
25160.22.7.208/2960.22.7.209 to 60.22.7.21460.22.7.2156
25260.22.7.216/2960.22.7.217 to 60.22.7.22260.22.7.2236
25360.22.7.224/2960.22.7.225 to 60.22.7.23060.22.7.2316
25460.22.7.232/2960.22.7.233 to 60.22.7.23860.22.7.2396
25560.22.7.240/2960.22.7.241 to 60.22.7.24660.22.7.2476
25660.22.7.248/2960.22.7.249 to 60.22.7.25460.22.7.2556

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.